Hillary Clinton faced her Republican critics today and made it clear she takes the death of U.S. diplomats on her watch very personally. The secretary of state spent hours and hours answering tough questions about the terrorist attack in Benghazi, Libya. The second round of testimony ended just a little while ago.

Now some lawmakers who have been demanding the hearings say they still are not satisfied.

It was tough at times. It was brutal at times. She answered the questions.

JAKE TAPPER, CNN CHIEF WASHINGTON CORRESPONDENT: That's right. Secretary Clinton said the State Department had significantly improved security for diplomats after the Benghazi attack, but the many questions that remain unanswered are likely to haunt the families of the victims and keep this issue for alive for Republicans.

(BEGIN VIDEOTAPE)

TAPPER (voice-over): More than four months after the deadly attack in Libya, Secretary of State Hillary Clinton today finally faced Congress.

HILLARY RODHAM CLINTON, U.S. SECRETARY OF STATE: I take responsibility.

TAPPER: In her first hearing since being sidelined by sickness, a concussion, and a blood clot, Clinton pushed back on the assertion that initially the Obama administration deliberately misled the public.

SEN. RON JOHNSON (R), WISCONSIN: And we were misled, that there was supposedly protests, and then something sprang out of that, an assault sprang out of that.

CLINTON: With all due respect, we had four dead Americans. Was it because of a protest? Or was it because of guys out for a walk one night and decided they would go kill some Americans? What difference at this point does it make? It is our job to figure out what happened and do everything we can to prevent it from ever happening again, Senator.

TAPPER: It makes quite a bit of difference, of course, in the context of the global terrorist threat throughout Northern Africa, including, now, Mali and Algeria.

CLINTON: There's no doubt that the Algerian terrorists had weapons from Libya.

TAPPER: It also makes a difference to those Republicans convinced that the administration was misleading.

To say that it's because an investigation was going on? The American people deserve to know answers, and they certainly don't deserve false answers.

CLINTON: We just have a disagreement.

TAPPER: Clinton may run for president in 2016. And today she faced two members of the committee with similar ambitions, Republican Senators Marco Rubio of Florida and a very aggressive Rand Paul of Kentucky.

SEN. RAND PAUL (R), KENTUCKY: Had I been president at the time, and I found that you did not read the cables from Benghazi, you did not read the cables from Ambassador Stevens, I would have relieved you of your post. I think it's inexcusable.

TAPPER: But today also brought moments of sorrow. Just days from her retirement, Secretary Clinton twice choked up, discussing the four Americans killed that night, Ambassador Chris Stevens, Sean Smith, Tyrone Woods, and Glen Doherty.

CLINTON: I stood next to President Obama as the Marines carried those flag-draped caskets off the plane at Andrews. I put my arms around the mothers and fathers, the sisters and brothers, the sons and daughters, and the wives left alone to raise their children.

TAPPER: Later this afternoon, in testimony before the House Foreign Affairs Committee, Clinton was more subdued and mostly welcomed by Republicans.

UNIDENTIFIED MALE: I wish you the best in your future endeavors, mostly.

(LAUGHTER)

TAPPER: Though there were moments of sparring.

REP. JEFF DUNCAN (R), SOUTH CAROLINA: Madam Secretary, you let the consulate become a death trap. And that's national security malpractice. CLINTON: I could have joined 18 of the other ARBs, under both Democratic and Republican administrations, kept it classified, and then, you know, just said goodbye. That's not who I am. That's not what I do.

TAPPER: Clinton's larger point, that Benghazi did not occur in a vacuum, and is emblematic of the larger challenge for the United States in Northern Africa.

CLINTON: We are in for a struggle, but it is a necessary struggle. We cannot permit Northern Mali to become a safe haven.

(END VIDEOTAPE)

TAPPER: Clinton made clear her view that despite the high risks, the U.S. cannot retreat in the Muslim world, which the late Chris Stevens knew better than anyone, Wolf.

BLITZER: But it's over for the secretary of state now. She did her five-and-a-half-hours of Q&A with members of the Senate, members of the House. Now she moves on. John Kerry's getting ready to start his own confirmation hearings.

TAPPER: Though, Wolf, there was a big 2016 subtext to all of this. If Secretary Clinton ultimately runs for president, this is not the last we have heard of this, not the last we have heard of that bite that we ran at the beginning of the piece. And of course, two members of the Senate who might run for president as well were asking her questions, Rand Paul, very aggressive, and Marco Rubio, who was a little bit more subdued.

BLITZER: Less aggressive Marco Rubio than Rand Paul.

So what you're saying is, potentially, if she decides to run for president in 2016, and a lot of us think there's a good chance she will, what she said today on Benghazi, the whole record since September 11 of last year, that could come back to, what, play a role in a campaign?

TAPPER: I would be surprised, if she runs, for that quote, where she says, what difference does it make, I would be surprised if that did not end up in a campaign commercial, a lot of Republicans already making hay out of it online and in press releases.

BLITZER: So it's not going away, by any means.

TAPPER: Absolutely not.

BLITZER: Jake, thanks very much.

There may be a chilling connection between the Benghazi attack and the hostage siege in Algeria that recently ended. There are now new unconfirmed reports that several Egyptian militants, Egyptian militants, were involved in both attacks.

Tom Foreman is taking a closer look at the security threat in North Africa.

Lay it out for us, Tom.

TOM FOREMAN, CNN CORRESPONDENT: Wolf, what security analysts are doing right now is essentially conducting a giant game of connect the dots, particularly looking at the area from Egypt to Libya to Algeria and down to Mali, down here, and looking at some events that have happened to say, is there something that ties them all together?

It starts back here on June 27 of last year, when Islamists seized control of Northern Mali. The Islamists who took control here in this country, which is 95 percent Muslim, are people who very much opposed the Arab spring. They did not like what they saw in many places, in large part because many of them believe that democracy is fundamentally anti-Islamic, because they want Sharia law. Democracy doesn't necessarily support that. Let's go to September 11.

That's when the attack came on Benghazi. And when the attack on Benghazi came, there was a different response from the folks in this area down here. What they saw at that time was that there was an attack waged in Libya, and at first, we thought it had to do with people based in Libya, but where did that attack come from? This latest news, as you mentioned, Wolf, relates now to the attack on the 13th, when the militants took hostages in Algeria.

There seems to be, based on these unconfirmed reports, a link between the fighters here and the fighters here and the weapons used here and the weapons used here. So what does that mean? Well, it's not entirely clear. What's unsure is whether or not that means that there is a firm connection or a loose connection, and security analysts are focusing on just a few groups here, Wolf, to see if they're the ones who are making all this work -- Wolf.

BLITZER: What do we know, Tom, about the people behind these attacks?

FOREMAN: Well, we don't know a whole lot. Security analysts, of course, do know more. But let's take a look at some of the possibilities here, as we take a look at the organizations.

The security challenges, there's no known command structure between these groups. We don't know the extent of cooperation. And we don't know the reach. How much further could they go, beyond that part of Northern Africa? But if we look at the groups involved, we have to look at Ansar al-Sharia. They are based in Benghazi, Libya.

This is the group that is believed to have the made the attack in Benghazi or to be somehow connected to it. They believe democracy is un-Islamic and they're believed to be connected to AQIM. AQIM is al Qaeda in the Islamic Maghreb. This is not necessarily connected to al Qaeda, even though it's in the name. This is a different group. They have a very strong presence in Mali.

They finance their rise largely by kidnapping Westerners and then demanding ransoms. So, again, when you look at all of these groups and you look at the terrain there, Wolf, what's happening right now is intelligence analysts are looking at these events and the groups and saying, is this happenstance that they all happened? Is it happenstance even that the same people might have been involved, or does this represent more cohesion, more organization, and a bigger terror threat -- Wolf.

Kate Bolduan is here, as she is every day, to dig a little bit deeper into the secretary's testimony today. And it went on and on.

KATE BOLDUAN, CNN ANCHOR: It went on and on, as you said, some five-and-a-half-hours of testimony. I want to listen here first to a little bit more of what Secretary Clinton said about the terror threat in Northern Africa.

(BEGIN VIDEO CLIP)

CLINTON: Benghazi did not happen in a vacuum. The Arab revolutions scrambled power dynamics and shattered security forces across the region. Instability in Mali has created an expanding safe haven for terrorists who look to extend their influence and plot further attacks of the kind we saw just last week in Algeria.

(END VIDEO CLIP)

BOLDUAN: Let's bring in our national security contributor, Fran Townsend. She's a member of the CIA External Advisory Board, and in August, Fran visited Libya with her employer MacAndrews & Forbes and met with Ambassador Chris Stevens shortly before the attacks in Benghazi.

Hi, there, Fran.

FRANCES TOWNSEND, CNN NATIONAL SECURITY CONTRIBUTOR: Hi, Kate.

BOLDUAN: Fran, how big of a problem is this? Are these kinds of incidents really now what we're seeing as the downside of the Arab spring?

TOWNSEND: You know, Kate, what interested me most about what Secretary Clinton was saying in that spot is that this is not a new problem in North Africa. Let's start with Mali.

You know, there was a safe haven along the Mali/Mauritania border that was controlled by Mokhtar Belmokhtar, who we have heard a lot about in recent weeks, going back when I was in the White House, you know, going back almost eight to 10 years ago, and we were engaged in a diplomatic effort, talking about with President Bouteflika of Algeria back then about the Algerians helping us to deal with that safe haven, which we were concerned about.

So there has been this period of time throughout the North African Maghreb in Algeria, Libya and Mali of this growing Islamist presence. Then the Arab spring comes along. Secretary Clinton is quite right. Security services melt away, borders become open, weapons become much more easily available. And the Arab spring acts as an accelerant to what is already a decade-long simmering problem of extremism throughout the Islamic Maghreb.

So this is not a new problem, is my point. And I think we shouldn't pretend that this is just a byproduct, an awful byproduct, of the Arab spring. This was a problem that was there long before that, but was accelerated, certainly, as a result of these sort of fledgling new governments.

BLITZER: Why isn't the Libyan government, Fran, doing more to detain, to arrest these -- especially the suspects involved in the Benghazi killing, but these al Qaeda operatives loosely affiliated with the core al Qaeda throughout Libya?

TOWNSEND: You know, Wolf, it's not just the Libyan government. Remember, the Tunisians had an individual in custody. Secretary Clinton was asked about that today, said, we're working with the Tunisian government. You know, we didn't have enough evidence yet to charge him.

FBI Director Mueller was in Libya last week, talking to the Libyans about the ongoing investigation. It's very frustrating to the families and to many who watch this. These investigations, these international ones, are complicated and they do take time. But believe me, Wolf, the bad guys in the region watch this. And the longer it goes without anybody being brought to justice, it's an indication to them that they have freedom of action, if you will, to target Western facilities and Westerners, and you see things like the attack on the Algerian oil facility.

BOLDUAN: So, Fran, I want to ask you, when you were watching this testimony from Secretary Clinton, this very lengthy testimony, hitting on so many topics, what was your big impression? What was your big takeaway from what you heard from her today?

TOWNSEND: You know, I put myself, Kate, in the position of the families who lost, you know -- Ambassador Stevens' family and the other families. And I think, more than anything, I was frustrated.

You know, they were asking -- the members of Congress were asking Secretary Clinton about talking points used by Susan Rice, which was an incredible waste of time. They often didn't seem terribly well prepared, and then when they did ask really good questions, she referred them back to this classified accountability review board report, which, of course, can't be spoken about in public.

So we didn't get a whole lot of answers. And I think -- I found it frustrating and I imagine, frankly, more importantly, the families found it frustrating, that this was a big show today, but I don't think we learned a whole lot new.

BLITZER: Senator Rand Paul, we spoke with him in the last hour, a member of the Foreign Relations Committee, he said that he would have fired her, had he been president, because she had not read the cables warning of security problems in Benghazi, including an appeal for more security from the late U.S. Ambassador Chris Stevens. When you heard that, what did you think?

TOWNSEND: You know, it was -- look, Wolf, she's the secretary of state. She's logged probably more miles than any prior secretary of state. She has a big staff.

What I didn't understand, though, was, we didn't hear anything about, where was the intelligence and research bureau of the State Department, who looks at these sorts of issues? Where was the diplomatic security and where was the undersecretary for management and the deputy secretary? Where were all those people who are in between the secretary of state and the sort of line people who have now been moved out of their positions, and why haven't they been held accountable?

Did they know about this? We really don't understand where inside the bureaucracy of the State Department that the buck stopped. And if -- Secretary Clinton rightly says she wants to take responsibility, but with responsibility ought to come accountability. And we didn't see much of that today.

BLITZER: Fran Townsend, thanks very much.

TOWNSEND: Thanks, Wolf.

BLITZER: Coming up, we're going to speak live with Greg Doherty, the brother of Glen Doherty. He died, he was killed in that Benghazi attack. We will get the brother's reaction to what Hillary Clinton said today in about 15 minutes.

BOLDUAN: Also ahead, many Americans are chilled to the bone right now. Stand by to find out how long the bitter cold temperatures will be lasting.

Also, the Beyonce lip-synching debate. Oh, what a debate. An inaugural official tells CNN about what he knows and he's very definite about what happened.

(COMMERCIAL BREAK)

BLITZER: It's not just the snow. It's the bitterly cold windchill temperatures, some in double-digit negatives. And that's impacting a large part of the country right now.

In some places, it's the worst we have seen in years. Indeed, it's so bad that Chicago firefighters struggled putting out a fire because the water instantly froze, leaving a sheet of ice on the side of a building. Similar scene in Minnesota, where a CNN iReporter had some fun tossing boiling water into the air and watching it turn into snow. He wasn't alone, by the way. Jeanne Moos is going to have more on this a little bit later.

Kate, I have got to tell you, people in my hometown of Buffalo, New York, they're used to the cold. I grew up in that kind of weather, but it's getting really, really cold right now.

In terms of how cold it is, about four degrees with the windchill here in New York City. It is very cold. But as cold as it is here, that is nothing in comparison to what folks are dealing with in the Midwest and other parts of the Northeast.

(BEGIN VIDEOTAPE)

CARROLL (voice-over): The Northeast sidelined by a Siberian express, more than 16 inches of snow in Erie, Pennsylvania, so much the plows can barely keep pace.

UNIDENTIFIED MALE: We keep crews going 24 hours, just to keep up with the snow, going back to the lots and redoing them over and over again.

With temperatures this low, throw a cup of hot water in the air in Fargo, North Dakota...

UNIDENTIFIED MALE: Oh, yes.

UNIDENTIFIED FEMALE: Hey.

CARROLL: ... and it appears to instantly turn to snow. The same problem in Chicago, temperatures so cold, firefighters struggled to put out a blaze when water from their hoses turns to ice. Windchill warnings and advisories now in effect for the Northeast, where hypothermia is a concern.

In Minneapolis, Doug O'Byrn says the cold weather goes with his jobs of maintaining the town's tree lights.

CARROLL: In New York City, dozens of warming centers opened to help those in need shelter from the cold. But those who have to be out say they're managing the best they can.

(on camera): You know, I keep hearing that. Keep moving.

UNIDENTIFIED FEMALE: Yes, keep moving, because then like you're not -- if you're standing cold, that's like all your body heat is staying still. But if you're moving, then your body heat is moving around and you stay warmer.

CARROLL: It's cold.

UNIDENTIFIED MALE: That is correct. That is correct. You can't feel your fingers at the end of the day.

(END VIDEOTAPE)

CARROLL: And you heard from what Chad was saying, the weather not expecting to improve until at least past this weekend.

So the city is really encouraging people here in at least New York City to take advantage of some of those warming centers that have been set up -- back to you.

BOLDUAN: All right, Jason. Thank you. Now it's time to go inside. Have a good night. We will talk to you soon.

BLITZER: Have some hot chocolate.

BOLDUAN: Have some hot chocolate, Wolf says.

Stand by for more on an historic change to the U.S. military.

(COMMERCIAL BREAK)

(NEWS BREAK)

BLITZER: We heard Secretary of State Hillary Clinton take responsibility once again for the deadly attack on U.S. diplomats in Benghazi, Libya. When we come back, we will ask the brother of one of the victims for his take on the secretary of state's testimony, whether he blames her, others, for his brother's death.

(COMMERCIAL BREAK) BLITZER: Happening now: another emotional take on the Benghazi attack, after Secretary of State Hillary Clinton's testimony. We're going to talk to the brother of one of the victims, Glen Doherty, and ask him who he blames.

Plus, an inaugural official now speaking out publicly about whether Beyonce lip-synched or not.

And Notre Dame football star Manti Te'o explaining why he lied about his fake girlfriend, even after he learned it was all a hoax.

I'm Wolf Blitzer. You're in THE SITUATION ROOM.

Hillary Clinton says it was very, very difficult to call the families of diplomats killed in the U.S. mission in Benghazi, Libya.

BOLDUAN: The secretary of state has wrapped up her long-awaited testimony before Congress. At one point, it got very emotional.

(BEGIN VIDEO CLIP)

HILLARY CLINTON, SECRETARY OF STATE: I stood next to President Obama as the Marines carried those flag-draped caskets off the plane at Andrews. I put my arms around the mothers and fathers, the sisters and brothers, the sons and daughters, and the wives left alone to raise their children.

BLITZER: And we're joined now by the brother of Glen Doherty. Greg Doherty is joining us from California. First of all, Greg, thanks for coming in. Our deepest, deepest condolences to you and your entire family.

GREG DOHERTY, BROTHER OF EMBASSY MASSACRE VICTIM: Thank you for that.

BLITZER: When you heard the secretary of state get emotional, speaking about your brother, the three others, what did you think of her testimony?

DOHERTY: Well, in that moment, I was remembering the really nice ceremony that they had for us on that Friday. We got to shake hands with her and the president and a lot of other people, and it was special. It was a really nice thing that they did for us.

BLITZER: Were the officials at the State Department keeping you informed of the investigation from day one?

DOHERTY: No. They told us some of the basics early on. They filled us in early the following week on more thorough details. A lot of it was coinciding with what was coming out in the newspapers, is how we were hearing it. We did have some people that were more on the inside, who were able to give us more details.

BOLDUAN: So, Greg, now after four months, since your brother's tragic death, and it's gotten caught up in, unfortunately, in such a horrible political controversy, what would you say is the one question or more than one question that you still have, that remains unanswered at this point?

DOHERTY: The political side of things, I guess, the main question that I would have is who did it and what's being done about it and how does this affect the way we're fighting this war on terror. I hear the name Ansar al Sharia as being the militia most closely associated with these attacks. I haven't heard many individuals' names. I don't know where anybody who did the attacking is. There was one man that was released, after being questioned. I think it was in Tunisia.

But, where the investigation is going and how we are proceeding, in dealing with also the big picture of just Islamist extremists in the Middle East and the African Maghreb (ph), I don't really -- I don't really understand how this is all working.

BOLDUAN: Yes. So what would you tell the secretary of state? What would you tell these members of Congress? What would you like to see being done?

DOHERTY: Well, the secretary of state, that role mainly seems to be about diplomacy. And I think the things that have been said about the, you know, inadequate security stance that they had there, they've been said, and the recommendations of the ARB board are being enacted, it seems, and those seemed reasonable.

It did seem clear that the consulate or the special mission, I guess it was, technically -- temporary mission, it technically was -- it wasn't adequately protected, but they know that. And they're hopefully funding, protecting other similar high-risk places.

The main thing I'm concerned about is just the big picture. How are we fighting this -- there's a lot of people that hate us out there, and what are we doing about it and how are we going after the people that are doing wrong against us? And how are we keeping more people from being recruited into that whole system?

BLITZER: Greg, had you ever heard from your brother, that he was worried about his security?

DOHERTY: Yes.

BLITZER: What did he say?

DOHERTY: He said that he didn't know -- well, you know, I said, how -- ugh. Yes, I don't know how to answer that question. He knew it was dangerous. He was -- but he was volunteering for it. So, it's just risky. It's a war zone.

BLITZER: Yes, he's a very -- he was a very, very courageous young man. I'm going to play a little clip. I interviewed Senator Rand Paul of Kentucky, a member of the foreign relations committee, earlier. But this is what he said to Hillary Clinton, during his questioning of her, earlier in the day.

(BEGIN VIDEO CLIP)

SEN. RAND PAUL (R), KENTUCKY: I'm glad that you're accepting responsibility. I think that, ultimately, with your leaving, you accept the culpability for the worst tragedy since 9/11. And I really mean that. Had I been president at the time and I found that you did not read the cables from Benghazi, you did not read the cables from Ambassador Stevens, I would have relieved you of your post. I think it's inexcusable.

(END VIDEO CLIP)

BLITZER: When you heard that, what was your reaction? Did you agree with the senator?

DOHERTY: I did not agree that I would relieve her of her post. I do agree that they should have had better communication. And not just within the State Department, but between the different departments, as well. The Department of Defense, the CIA. Everyone, it seems like they could be communicating a lot better with each other.

BOLDUAN: Greg, I'm sure, on some level, everyone who's lost someone in this tragedy is searching for someone to hold accountable. Someone to blame. So who do you blame? Do you blame the secretary of state? Who do you blame?

DOHERTY: I blame Ansar al-Sharia or the terrorists who were pulling the trigger.

BLITZER: You blame the killers. But in terms of the lax security, is there somebody you're blaming for that?

DOHERTY: I think people are sorting that out. Yes, I think there are people who should be blamed. I'm not really clear, though, on where that all falls.

They -- they should have designated this a permanent consulate, instead of a temporary facility. That would have left some clear standards in place about the personnel that should have been there and the physical reinforcements they should have had at the place.

They should have had more people on board, and I'm not sure where that gets funded from, and I'm not sure who approves that funding. But I think it was Democrats, Republicans, State Department, Department of Defense, they all share responsibility for it.

BLITZER: Well said. Greg Doherty, once again, our deepest condolences to you, to your entire family. Thanks very much for joining us.

DOHERTY: Thank you.

BLITZER: We'll take a quick break. Much more news right after this.

(COMMERCIAL BREAK)

(BEGIN VIDEO CLIP)

(MUSIC: "STAR-SPANGLED BANNER")

(END VIDEO CLIP)

BLITZER: An inaugural official telling CNN the pop star Beyonce did, in fact, lip sync her performance on inauguration day.

BOLDUAN: That's true. CNN national political correspondent Jim Acosta's been following this story. The drama continues. What do you have?

JIM ACOSTA, CNN CORRESPONDENT: First, let me tell you about this interview that we conducted earlier today. In an exclusive interview with CNN, the owner of the audio company at Monday's inaugural says he knows whether Beyonce was live or lip syncing, but he won't say.

But we did talk to an inaugural official who did confirm to CNN the pop star was lip syncing on inauguration day.

(BEGIN VIDEOTAPE)

BEYONCE, SINGER (singing): Oh, say can you see by the dawn's early light...

ACOSTA: Beyonce may still be holding her tongue over whether she was actually singing the national anthem on inauguration day, but Bob Goldstein, the owner of the company that provided the audio equipment for the ceremony, says he knows the truth. Goldstein would not go on camera, but fittingly, he spoke to CNN in this audio-only interview.

BOB GOLDSTEIN, OWNER, MARYLAND SOUND INTERNATIONAL (via phone): What people heard over the system and on air was Beyonce singing the, you know, the national anthem, and when she actually sang it is kind of a moot point. It was her. It wasn't done with 15 takes. It was her, all the way live, at some point in time, and only she can tell you when that was.

ACOSTA: The day after the inaugural, the U.S. Marine Band initially said the pop star did not actually sing "The Star-Spangled Banner" and that a prerecording was used instead, but the band leader backed away from the statement, saying it could not make that determination.

Goldstein declined to definitively say whether Beyonce was live or lip synching, but he did allow CNN to get these shots of the audio board that was used for the ceremony.

(on camera) One way to answer this question, once and for all, is to find out which fader the audio technician turned up? Was it the one for the prerecording or the one for Beyonce? Officials here say the audio engineer actually running this board works for another company.

(via phone): Can you give us any clarity on that?

GOLDSTEIN: Boy, I'm really sorry, that I can't. I'm really sorry that I can't. I don't -- I don't believe it's up to us to have that conversation. I mean, you know, I don't think it's a question that I should answer.

ACOSTA: And is it because you just feel like, you know, this is -- this is something for somebody else to disclose and talk about and not...

GOLDSTEIN: Well, I think it's -- I think it's something that Beyonce should disclose. I think it's up to her whether she wants to, you know -- I mean, trust the conversation.

ACOSTA: Could he hear her singing into the microphone?

GOLDSTEIN: I don't think I'm going to answer that question.

BEYONCE (singing): My country, 'tis of thee...

ACOSTA (voice-over): One thing Goldstein did say is that the day's other two big performers, Kelly Clarkson and James Taylor, were, indeed, live.

GOLDSTEIN: I can tell you that the other two were absolutely all the way live.

ACOSTA: Just can't tell us about Beyonce?

GOLDSTEIN: I can't tell you about Beyonce, because it's become an issue.

ACOSTA: But an inaugural official who asked not to be identified was willing to go further on Beyonce's performance, telling CNN the pop star made the decision to use the prerecording the night before the inaugural.

That official said, "Because she didn't have time to rehearse with the Marine band, she decided to use her recording with the Marine Band. She did not sing live."

Up on Capitol Hill, congressional officials overseeing the inaugural are still refusing to answer any questions on what some are now calling Beyonce-gate. There were no loose lips over at the White House either.

JAY CARNEY, WHITE HOUSE PRESS SECRETARY: I'm not sure that I understand the variety and contradictory reports on the matter.

(END VIDEOTAPE)

ACOSTA: Music industry experts say it's not uncommon for performers to lip sync at big outdoor events. Still, Beyonce's publicists have yet to return CNN's request for comment. And Wolf, it almost is sort of a twist on the old term, it's not the crime, it's the cover-up. In this case, it's not the concert, it's the cover-up, it seems.

BLITZER: At least it's been resolved. Whether she issues a public statement, we now know for sure what happened.

ACOSTA: We do now know for sure, according to this one inaugural official. Unfortunately, the other officials who are in charge of this, some of the public officials, aren't willing to say definitively on camera, but from this one inaugural official, yes, she was lip syncing.

(CROSSTALK)

BLITZER: Just to be precise, it's her voice. She does a beautiful job.

BLITZER: Manti Te'o explaining now why he lied about a girlfriend after he knew she didn't exist. He's speaking out. So is the woman whose picture helped fuel the -- so is the woman's picture helped fuel the alleged case.

BLITZER: Brian Todd is here. He's been working this story. What's the latest, Brian?

BRIAN TODD, CNN CORRESPONDENT: Wolf and Kate, Manti Te'o is still firmly denying that he is part of this hoax, but he does admit he was not forthcoming with the public, even after he got a crucial piece of information.

(BEGIN VIDEOTAPE)

TODD (voice-over): Manti Te'o says he stuck to the story about a girlfriend he'd never met, briefly telling the media and the public about her, even when he knew something was wrong. In an interview with ABC's Katie Couric, Te'o was asked why.

MANTI TE'O, NOTRE DAME FOOTBALL PLAYER: This girl, who I committed myself to, died on September 12. Now I get a phone call on December 6 saying that she's alive and that I'm going to be put on national TV two days later, and they ask me about the same question, you know, what would you do?

TODD: A source with knowledge of the matter tells CNN, a woman pretending to be Te'o's apparent girlfriend, Lennay Kekua, called him on December 6, claiming she had faked her death because she was afraid of drug dealers. Te'o went to Notre Dame officials with the story. The school investigated and, according to our source, confirmed that two men and a woman were behind the hoax.

Te'o says he didn't believe that his online girlfriend never existed until Deadspin.com first reported it on January 16.

Now the woman who says her Facebook pictures were used to depict the fictional girlfriend on Twitter has told NBC News she wasn't part of the hoax and never met Manti Te'o. Diane O'Meara says this man, Ronaiah Tuiasosopo, an acquaintance from high school, is behind the scheme.

DIANE O'MEARA, PHOTO USED IN HOAX: The past five years, he's literally been stalking my Facebook and stealing my photos.

TODD: O'Meara said Tuiasosopo called her, confessed and apologized. Manti Te'o and Deadspin say Tuiasosopo is behind the hoax. CNN's source says Notre Dame's investigation has confirmed that he was one of the people behind it.

(on camera): CNN has tried several times to reach Ronaiah Tuiasosopo. He has not responded. His father, Titus, a pastor, whose picture is here on Facebook, would not go on camera with us, but did tell us, quote, "The truth will all come out. God knows our character."

(voice-over): Te'o has denied being part of the hoax. I asked crisis management expert Eric Desenhall about the Couric interview.

TE'O: What would you do?

TODD (on camera): How did he come across to you?

ERIC DESENHALL, CRISIS MANAGEMENT EXPERT: You know, there's a difference between being young and foolish and being Machiavellian and scheming. He comes across as a guy who probably was young and foolish. While we don't know what the data trail is going to show. That remains to be seen.

(END VIDEOTAPE)

TODD: And in fact, some key questions remain. Did Manti Te'o and Ronaiah Tuiasosopo know each other before all this broke? A distant cousin of Ronaiah Tuiasosopo told me that the families do know each other, but we've not gotten any details beyond that.

The other key question, who's the person posing as Te'o's girlfriend who Te'o says he spoke to on the phone many times? Answers we're still digging on -- Wolf and Kate.

BLITZER: And there's another woman whose pictures were apparently stolen to create the identity of someone else. What's this part of the story?

TODD: Getting even more bizarre when we thought it couldn't. Her name is Donna Tei, not Te'o, Te-"I". She was identified in pictures in a Twitter account portrayed as the sister of the girlfriend. Another fictitious sister of a fictitious girlfriend. She has denied meeting Manti Te'o and says she was not part of the hoax. Her pictures were used in Twitter depicting her as the sister of the girlfriend, just if you're scoring this at home.

BOLDUAN: We need a flowchart. Thank you.

BLITZER: All right. Thanks very much.

BOLDUAN: Brian, thank you.

To another big story we've been following this evening. Hillary Clinton on the hot seat over the Benghazi attack. One specific senator riled up the secretary of state earlier today. He's going "OUTFRONT" with Erin Burnett tonight. Erin's here with a little bit of a preview.

Hi there, Erin.

ERIN BURNETT, CNN ANCHOR: Hi there, Kate.

And yes, Senator Ron Johnson came out today with a very testy exchange with the secretary of state. In fact, he left Hillary Clinton literally pounding her fists on the table. Very emotional. And she actually began a response with the words, Kate and Wolf, with the words "with all due respect." That's one of my favorite phrases. Usually, when it's used, it means anything but. Not usually the nicest phrasing to use.

But it was a very emotional exchange, and we're going to be talking with the senator about what he talked about with the secretary of state and whether this country got the answers it needs on Benghazi.

So that's coming up at the top of the hour. Back to you.

BOLDUAN: That was a huge story today. What else do you have coming up at the top of the hour?

BURNETT: Well, we're also going to be talking about Manti Te'o and sort of find out is it possible, now that we got this little trickle of what happened, when he said, "Yes, I lied, but only about this." Where there's one lie, is this going to be a whole lot of lies? Sort of like cockroaches. There's never just one. We're going talk to Dr. Drew Pinsky about that.

And women in combat. One man who says, with the wars we're going to be fighting, rape is going to be one of the biggest risks Americans face. And this is a tough question to have. As a woman, it's one I've been torn on over the years. But we're going to talk about that. Women in combat and whether women really should be on the front lines.

BOLDUAN: There's quite a debate about it, but it's a good conversation to be having. "ERIN BURNETT OUTFRONT" at the top of the hour. See you soon. Thank you.

We showed you earlier all the cold weather misery, but for some, it seems to be an excuse to have a little fun. Jeanne Moos takes a look, coming up next.

(COMMERCIAL BREAK)

BOLDUAN: Our video of the day is a time lapse. Look at this. Showing fog rolling across Dubai. The city state is on the southeastern corner of the Arabian Peninsula, along the Persian Gulf, which sets up some clearly pretty interesting weather patterns. If you were in a tall enough building -- and Dubai has plenty, including the world's tallest -- the view was great.

BLITZER: You been to Dubai?

BOLDUAN: That looks like the beginning of a sci-fi movie. No. You going to rub it in my face? You have. Really?

BLITZER: Amazing (UNINTELLIGIBLE).

Those of us on the ground here in the United States are coping with one of the coldest winters in years. Some folks are coping with what our own Jeanne Moos calls stupid weather tricks.

(BEGIN VIDEOTAPE)

JEANNE MOOS, CNN CORRESPONDENT (voice-over): Why just charge through the cold when you can use it to experiment? It used to be civilians, posting their weather tricks online. But these days, actual weather men are demonstrating what happens when you throw boiling water in temperatures below zero.

MOOS (on camera): But anyone who plans to try this one when it's warmer than, say, 20 or 30 degrees before zero, better bring an umbrella to avoid risking second-degree burns.

(voice-over): Swimming around the Internet, you'll see giant bubbles crystallizing in the cold. You'll see what a super-soaker does at sub-zero.

UNIDENTIFIED MALE: Go for it.

MOOS: But the most popular stupid weather trick this season seems to be the frozen wet T-shirt.

UNIDENTIFIED MALE: Take a look. It took less than ten minutes for it to completely freeze over here.

UNIDENTIFIED FEMALE: It only took six minutes.

UNIDENTIFIED MALE: Which we can now hold upside down, because it is frozen solid. It took two, three minutes.

MOOS: If frozen T-shirts leave you cold, how about a frozen banana? Instead of a hammer or a frozen egg in Minnesota, where it was 20 below. Of course, an egg freezes. It would be news if it didn't. But it looks funny.

Or if it's egg on your face you prefer, show up on TV in a funny hat.

UNIDENTIFIED FEMALE: That is a serious piece of business and it looks good, too.

UNIDENTIFIED MALE: It's best like that, Kevin.

UNIDENTIFIED MALE: Now, I may look like a bank robber tonight, Scott.

MOOS: Just last week, Jimmy Kimmel was making fun of Southern California news anchors for freaking out when temperatures dipped into the 50s and lower.

UNIDENTIFIED MALE: Cold, cold, cold coming our way.

UNIDENTIFIED FEMALE: We have team coverage on this freezing cold weather.

UNIDENTIFIED FEMALE: The extra blankets, the Cheetos (ph), the dog, anything you can do to keep warm. Snuggle.

UNIDENTIFIED MALE: How long will this arctic blast last?

MOOS: Long enough for us to beat the frozen T-shirt into the ground.

UNIDENTIFIED MALE: It is solid.

UNIDENTIFIED FEMALE: I'll confirm. It's frozen.

MOOS: Jeanne Moos...

UNIDENTIFIED MALE: You look like Mickey Mouse.

MOOS: ... CNN...

UNIDENTIFIED MALE: OK. Look at that! Whoa! MOOS: ... New York.

(END VIDEOTAPE)

BLITZER: You grew up in Indiana. I grew up in Buffalo. You know when it's January, it's winter. It gets cold.

BOLDUAN: Not getting any sympathy from us today.

BLITZER: Don't even want to talk about it.

BOLDUAN: I know. He always gets like this.

BLITZER: Thanks very much for watching. That's it for us today. Remember, you can always follow us on Twitter, if you want. You can tweet me, @WolfBlitzer.